Promote Clean Ocean Water

Restore Native Fish

Clean ocean water is essential for healthy coral reefs. It’s also important to visitors and residents who enjoy swimming, snorkeling, diving, paddling, fishing and surfing along Maui’s coasts.

Maui Nui Marine Resource Council is proud to be a major partner in an innovative community-based water quality monitoring program called Hui O Ka Wai Ola (Association of Living Waters).

Filling an important need

Download our 2016 – 2018 Coastal Water Quality Report

The Hui O Ka Wai Ola program is a living breathing example of how nonprofit organizations can effectively work with government agencies to stretch the agencyʻs resources and capabilities.

Maui Nui Marine Resource Council, The Nature Conservancy and West Maui Ridge 2 Reef co-manage the Hui O Ka Wai Ola program to support the State of Hawaii Department of Health Clean Water Division.

Together with the help of more than 40 volunteers from the community, Hui O Ka Wai Ola has greatly expanded the Department of Healthʻs ability to test ocean water quality at Maui beaches and to provide quality-assured data to County, State and Federal agencies.

We add to the data collected by the Department of Health with our testing that keeps a close eye on changing water quality conditions that can harm our coral reefs.

Our community-based program regularly gathers data about sediment, nutrients in the water, temperature, pH and more at 39 locations along Mauiʻs south and west shores. Starting in 2019, weʻll be expanding our program to include testing for enterococcus bacteria at our South Maui testing sites.

We believe this data will allow for more effective management of our nearshore waters and ultimately, healthier coral reefs and cleaner ocean water for all to enjoy.

Note: the red dotted lines indicate standards set by Hawaii’s Department of Health Clean Water Division.

What We Test For

Turbidity

How it is measured: We gather samples at knee depth, then use a turbidity meter onsite to measure the amount of sediment (turbidity) in the water.

How changes are caused: Sediment carried from the land to the ocean (by streams, flooding, storm runoff) can cause ocean water to become brown or murky.

Why it is a concern: Sediment blocks sunlight from reaching reefs and can smother corals.

What we can do: When we find areas with high levels of turbidity, we can address upslope issues such as grading or clearing of land that caused sediment to flow into the ocean.

Ocean chemistry

How it is measured: We measure pH, salinity and water temperature onsite using portable, handheld equipment.

How changes are caused: Changes in ocean chemistry can be caused by climate change and other local factors. Salinity can be changed by freshwater flowing into the ocean. Water temperature can fluctuate by season and can also be caused by climate change. Ocean acidity can be increased warming ocean temperatures. Warmer water also holds less dissolved oxygen (needed for aquatic plants and animals to survive).

Why it is a concern: Corals are very sensitive to changes in ocean chemistry, including increased ocean water acidity. Corals bleach when water temperature increases; collecting water temperature can help track localized variations between sites.

What we can do: We can monitor changes in reef health against changes in ocean water quality and continue to advocate for ways to reduce greenhouse gases and reverse climate change.

Nutrients (nitrogen and phosphorous)

How they are measured: Water samples are gathered, refrigerated and shipped on ice to the SOEST Analytical Laboratory on Oahu for analysis of nitrogen and phosphorous.

How changes are caused: High levels of nitrogen and phosphorous can indicate pollution from wastewater, run-off from agriculture, landscaping and/or golf courses. T

Why itʻs a concern: Too much nitrogen can cause an increase in invasive algae (limu), which is damaging to coral reefs.

What we can do: When we identify ocean areas with high levels of nutrients, we can pinpoint and address up-slope areas that are sources.

Bacteria

How it is measured: Water samples are gathered in sterile bags, which are then sealed and refrigerated. Samples are shipped on ice to regional labs, where they are analyzed for Enterococcus bacteria.

How it is caused: Bacteria may result from wastewater pollution. Enterococcus bacteria also live in soil and can be carried into the ocean via runoff.

Why itʻs a concern: Enterococcus bacteria are generally not harmful by themselves but do indicate the possible presence of pathogenic (disease-causing) bacteria, viruses, and protozoans that also live in human and animal digestive systems.